The objective of this proposed work is to determine what mechanisms on the surface of the host and bacteria govern the establishment of an acute and chronic bladder infection. Rat bladders will be chemically and mechanically altered and the interaction with such bladders studied by light and scanning electron microscopy. Competitive inhibition and enzymatic degradation of both urothelial and bacterial cell receptors will be studied to garner information on the chemistry of the receptors. Biochemical methods, column chromatography and gel electrophoresis will be used to purify, identify and collect receptors for use as immunogens. The antibody response to pathogens will be studied by immunological techniques in an effort to determine the quantitative and qualitative immunological response. Antibody concentrations will be suppressed by azathioprine or enhanced by vaccination to determine their role in suppressing infections. Chronic urinary tract infection will be established in rats by surgically placing a foreign body in the bladder. Vaccination, chemical alteration of the bladder surface, blocking of bacterial adherence, antibody quantitation and localization will be attempted with this model to elucidate the host parasite relationships in chronic urinary tract infections. In addition, human urinary tract tissues will be compared and contrasted with the rat bladder models to compare and contrast human infections with those induced in the rat model.